Guns are very dangerous weapons. China has strict control over guns. However, guns are not controlled in some countries, such as the United States. Therefore, there are frequent shooting incidents in the United States. If a shooting incident occurs, the masses have no daily necessities to withstand the shooting, which leads to the masses having no protective measures during the shooting.
The existing bulletproof backpack can only prevent bullets on the back, but cannot prevent bullets both on the front chest and on the back, so the existing bulletproof backpack is low in security.